import java.util.HashSet;

//TIP 要<b>运行</b>代码，请按 <shortcut actionId="Run"/> 或
// 点击装订区域中的 <icon src="AllIcons.Actions.Execute"/> 图标。

public class Main {
    public static void main(String[] args) {

        HashSet set = new HashSet();
        Student st1 = new Student(11,"wei");
        Student st2 = new Student(12,"wei");
        Student st3 = new Student(13,"wei");
        set.add(st1);
        set.add(st2);
        set.add(st3);

        System.out.println(set);
    }
}